The invention relates to a forced air flow ventilation system. More specifically, it refers to the employment of two or more blowers mounted on a frame having an air flow pattern such that the air from separate blowers turning in different directions impinge upon each other at varying angles to produce a wide fan pattern of air.
Typically, prior art fans or blowers are mounted to expel blown air directly in front of the blower. In U.S. Pat. No. 5,370,576 a pair of truck cab blowers are mounted one above the other to force outside air into the truck cab. Fan housing cover plates are pivoted to either an open or closed position. Air flow adjustment members 74 and 76 are rotated to independently adjust the air discharge direction. There is no suggestion for rotating the air flow adjustment members so that the air flow from separate blowers impinge upon each other. In U.S. Pat. No. 5,643,082, a series of blowers or fans are installed in a building wall in separate frames. Each blower emits an air stream into the building directly from the front of the blower. There is no air flow from adjacent blowers that impinge upon each other.
The air flow pattern from separate blowers is limited by the size of the blower and the position of the blower with respect to its target. A system is needed which will extend the flow pattern to a wider area from a given number of blowers.
The present invention provides a system for expanding the flow pattern of a pair of blowers so that a greater area is affected by the impingement of the blower air streams. Therefore, the air flow area covered by the two impinging air streams is greater than the sum of the air streams for the two blowers acting independently, side by side.
A pair of blowers are pivotally mounted one above the other in a vertical frame structure. The fan blades in one blower turn clockwise and the fan blades in the other blower turn counterclockwise. The blowers have a protective grate in front of multiple blades, but no other structure impedes the flow of air from each blower. The blowers are locked in place at an angle of 10 to 60 degrees with respect to each other so that air emanating from the blowers impinge on each other at a point spaced from the front of the blowers. This impingement creates a fan-like pattern that expands outwardly and downstream from the impingement point.